How to get user preferences path from blender
Using: bpy.utils.resource_path('USER')

eg:

import os
import bpy

user_path = bpy.utils.resource_path('USER')
config_path = os.path.join(user_path, "config")



Or on Linux:/home/user_name/.config/blender/2.74
On ms-windows will return:C:\Users\user_name\AppData\Roaming\Blender Foundation\Blender\2.74


See: bpy.utils.resource_path api docs